[FLINK-40271][table] Fix SQL serialization of Table API group window properties

[Timm0]

What is the purpose of the change

Table API group-window properties — $("w").start(), $("w").end(), $("w").rowtime() and $("w").proctime() — were not translated to the corresponding windowing-TVF output columns when a WindowAggregateQueryOperation is serialized back to SQL. The group window alias was emitted as if it were a column reference, so the generated statement failed to validate with Column 'w' not found in any table. This change maps each property onto the TVF's window_start / window_end / window_time columns and adds window_time to the GROUP BY when it is projected, so the serialized SQL parses and produces the same results as the Table API program it came from.

Brief change log

• Serialize window properties to the windowing-TVF output columns window_start, window_end and window_time instead of emitting the group window alias, which produced unparseable SQL
• Add window_time to the GROUP BY when a rowtime()/proctime() property is projected
• Reject a proctime() property on an event-time group window with a TableException
• Add TableTestProgram#getRunTableApiTestStep
• Add rowtime and proctime serialization test programs, plus semantic coverage of the generated SQL for the rowtime case

Verifying this change

• New tests in QueryOperationSqlSerializationTest and QueryOperationSqlSemanticTest

Does this pull request potentially affect one of the following parts:

• Dependencies (does it add or upgrade a dependency): no
• The public API, i.e., is any changed class annotated with @Public(Evolving): no
• The serializers: no
• The runtime per-record code paths (performance sensitive): no
• Anything that affects deployment or recovery: JobManager (and its components), Checkpointing, Kubernetes/Yarn, ZooKeeper: no
• The S3 file system connector: no

Documentation

• Does this pull request introduce a new feature? no
• If yes, how is the feature documented? n/a

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Was generative AI tooling used to co-author this PR?

• Yes

Generated-by: Claude Code Opus 5 (1M context)

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CI report:

• 91115b2 Azure: SUCCESS

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